﻿Shader "Unlit/FireFlyNew"
{
    Properties
    {
        _MainTex ("Albedo (Emissive)", 2D) = "white" {}
        _Wings ("Wings", 2D) = "white" {}
        _EmissiveAmount ("_EmissiveAmount", Float) =2.0
    }
    SubShader
    {
        Tags { "Queue"="Transparent" "IgnoreProjector"="True" "RenderType"="Transparent" }
        LOD 100

        Pass
        {
            CGPROGRAM
            #pragma vertex vert alpha:fade
            #pragma fragment frag

            #include "UnityCG.cginc"

            struct appdata
            {
                float4 vertex : POSITION;
                float4 uv : TEXCOORD0;
                float4 color : COLOR;

                UNITY_VERTEX_INPUT_INSTANCE_ID
            };

            struct v2f
            {
                float4 uv : TEXCOORD0;
                float4 vertex : SV_POSITION;
                float4 color : COLOR;

                UNITY_VERTEX_OUTPUT_STEREO
            };

            sampler2D _MainTex;
            float _EmissiveAmount;

            v2f vert (appdata v)
            {
                v2f o;

                UNITY_SETUP_INSTANCE_ID(v);
                UNITY_INITIALIZE_OUTPUT(v2f, o);
                UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(o);

                o.vertex = UnityObjectToClipPos(v.vertex);
                o.uv = v.uv;
                o.color.rgba = v.color.rgba;
                return o;
            }

            fixed4 frag (v2f i) : SV_Target
            {
                UNITY_SETUP_STEREO_EYE_INDEX_POST_VERTEX(i);

                fixed4 col = tex2D(_MainTex, i.uv);

                float4 emissive = i.color * col.a;

                clip(i.color.a - 0.5);

                col += emissive * pow(_EmissiveAmount, 2.2);
                return col;
            }
            ENDCG
            }

        Pass
            {
            Cull Off
            Blend SrcAlpha OneMinusSrcAlpha

            CGPROGRAM

            #pragma vertex vert
            #pragma fragment frag

            #include "UnityCG.cginc"

            struct appdata
            {
                float4 vertex : POSITION;
                float4 uv : TEXCOORD0;
                float4 color : COLOR;

                UNITY_VERTEX_INPUT_INSTANCE_ID
            };

            struct v2f
            {
                float4 uv : TEXCOORD0;
                float4 vertex : SV_POSITION;
                float4 color : COLOR;

                UNITY_VERTEX_OUTPUT_STEREO
            };

            sampler2D _Wings;

            v2f vert (appdata v)
            {
                v2f o;

                UNITY_SETUP_INSTANCE_ID(v);
                UNITY_INITIALIZE_OUTPUT(v2f, o);
                UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(o);

                o.vertex = UnityObjectToClipPos(v.vertex);
                o.uv = v.uv;
                o.color.rgba = v.color.rgba;
                return o;
            }

            fixed4 frag (v2f i) : SV_Target
            {
                UNITY_SETUP_STEREO_EYE_INDEX_POST_VERTEX(i);

                fixed4 wings = tex2D(_Wings, i.uv.zw);
                wings.a = lerp( wings.a, 0, i.color.a);

                return wings;
            }
            ENDCG

        }
    }
}
